Determination of total thallium in soils by atomic emission spectrography using a two-jet arc plasmatron

Abstract

A procedure is proposed for the direct determination of total thallium in solid soil samples by atomic emission spectrography with spectral excitation in an two-jet argon-arc plasmatron. The conditions for spectrum excitation and registration have been optimized. The analytical possibilities of the two zones in the plasma jet, before and after the jet confluence, were compared using the determination of thallium in soils as an example. Reference samples were artificial mixtures prepared on the basis of real soils. The accuracy of the results was estimated using the t-test in the analysis of samples with the known analyte concentrations. The experimentally found detection limit is 0.3–0.5 mg/kg. The relative standard deviation at an insignificant systematic error is 12–15% (n = 20; P = 0.95).